In July, a panel of U.S. government researchers said that the ocean is becoming more acidic as it absorbs carbon dioxide released by cars, factories, and power plants. The increased acidity can dissolve the calcium exoskeletons of tiny coral and plankton, which experts say could substantially alter undersea life by eliminating a vital link in the food chain.

Higher water temperatures are also causing widespread coral "bleaching" around the world, from Australia's Great Barrier Reef to the Caribbean,
which in 2005 suffered the worst bleaching ever recorded. The elevated temperatures can eventually kill the coral and in turn eliminate habitat for a variety of sea creatures.